Light modulator/deflector using acoustic surface waves

摘要

A light modulator/deflector which uses acoustic surface waves wherein an illuminating beam 10 enters the side of and strikes the active surface 18 of a transparent, piezoelectric, and electrooptic acoustic substrate 12 near the grazing angle of incidence and is reflected off that surface 18 through the remaining portion of substrate 12 and out the other side thereof into at least a zero order undiffracted direction and a first order diffracted direction. For a modulator the light 10 is made to converge in the plane of incidence so that it comes to focus on the active surface 18 of the acoustic device. For a deflector, the light 10 is collimated so that it interacts with as much of the acoustic wave 20 as possible. A set of interdigital electrodes 16 is evaporated on this surface 18 so as to launch acoustic waves 20 in a direction normal to the plane of incidence of the light.